Finding the Fourth Proportional to 111.35, 166.55 and 103.15

Step by Step Solution

1. Step 1: Write the proportion equation
   111.35 : 166.55 = 103.15 : x
2. Step 2: Convert to fraction form
   111.35/166.55 = 103.15/x
3. Step 3: Cross multiply
   111.35x = 166.55 × 103.15
4. Step 4: Simplify right side
   111.35x = 17,179.32
5. Step 5: Solve for x
   x = 17,179.32/111.35
6. Step 6: Final answer
   x = 154.28